The Multicolored Asian
lady beetle, Harmonia axyridis. This species has become quite a
nuisance in the United States even though it is a voracious predator.
Multicolored Asian Lady Beetle was intentionally imported from Russia,
Japan, Korea, and elsewhere in the Orient and for releases in the United
States as part of a Federal effort to naturally control insect pests in
trees. With the first releases (1916 and 1960) the beetle did not
establish. The in the 1970s and the early 1980s, tens of thousands
of these beetles were intentionally released by the U. S. Department of
Agriculture's Agricultural Research Service (USDA-ARS) in an effort to
control insect pests that injure trees. All did not go as planned, as many
home owners found out.
In their native countries these
beetles over winter on cliff faces and crevices, here in the US they have
taken to buildings to over winter. They are attracted to light colored
light-colored walls with a south or southwest exposure. They settle down
into the dark cracks to over-winter.
This means in the winter they are likely to crawl into
the inside of houses,
invading homes becoming an annoyance to the human inhabitants. Recent
studies have shown that their attraction is not strictly to white
or light colored homes, but more the strong vertical contrasts made in
late afternoon, when their urge to migrate is strongest. Homes or
structures with vertical columns, dark colored shutters against a light
background, or strong vertical shadows simulate trees against a
mountainside, resemble their natural hibernation destination in Asia.
(study done by Joe Kovach and Margaret Huelsman of Ohio State)
the walls they are more likely to become active on warm winter days. When
they are in your home they will not feed or breed but die. They do not
do structural damage, nor do they lay eggs indoors. When indoors they are
hard to control, so prevention is important.
Multicolored Asian lady beetles have
also been reported to nibble or "bite" humans. They are not aggressive,
but may taste to seek moisture. They will not break the skin or draw blood
nor cause health problems.
Do not swat or smash lady beetles.
They have yellow body fluids that can stain walls and fabric.
Control: Caulking up cracks and other
opening that allowing them into the walls will help. Inspect the
outside of building from top to bottom and screen or seal any openings
small enough to admit the beetles. Don't for get the roof lines. If they are inside
they can be removed by vacuuming or by use of a black light trap.
Want to built a trap? Trapping system for flying insects.
I have heard people recommend
everything from bay leaves or basil in window sills to stuffing
cotton balls with camphor essential oil on them in the entry holes.
People even use Ben Gay around window to repel (Ben Gay has both
camphor and menthol) What these products are doing is keeping the
beetles from entering your home, which studies have show camphor and
menthol do repel lady beetles.
Multicolored Asian lady beetle
Larva of the
Multicolored Asian lady beetle
This beetle is
typically orange-red with or without spots or may only
have traces of 4 spots. They all have a black “M” on the white area
just behind the head.